CHI3L1 and Bartsocas-Papas syndrome 1: Serum levels of proteins involved in ECM degradation, including MMP9 (p = 0.0242) and CHI3L1 (p = 0.0284), involved in tissue repair, as well as adhesion molecule ICAM1 (p = 0.0014) were significantly higher in IC/BPS patients compared to controls.